240 
J. A. COUTURE. 
^ [Written Specially for the American Veterinary Review.] 
DISEASES OF THE HEART AND BLOOD VESSELS. 
IV. 
THICKENING OF THE COATS OF THE AORTA (ARTERIO-SCLE- 
rose) causing, as the main symptom, attacks 
OF STAGGERS. 
By J. a. Couture, V. S., Quebec. 
On March 7, 1893, I was called to attend a draught mare, 
aged five years, weight 1400 lbs., presenting all the appearanees of 
perfeet health. The history of the case was as follows : Until 
February 15, this mare had been used as a light dranghter, 
working very well, but very hard. That day she had during 
the journey an attack of staggers, as the owner caUed it; she 
fell on the ground, was bled at the palate and recovered her 
senses after a few moments. The journey was finished without 
J ' mo. e trouble. 
The next day, February i6th, she was travelling at a good 
speed when she had another attack of staggers ; a few minutes 
of rest, another blood-letting of the palate, and the mare con¬ 
tinued her journey back home. She had to cover three miles 
to return to the stable ; the distance could be travelled at a walk 
only, as the mare was having new fits of staggers as soon as she 
was made to trot. 
The patient was given a fortnight’s rest, during which time 
nothing remarkable was noticed by the owner. The appetite 
was good, the faeces normal, the eyes bright, the animal appear, 
ing in the best of health. 
She then returned to her work, but was found of no use. 
She could only pull her vehicle, at a walk, for 40 or 50 acres, 
and would then show a most intense dyspnoea, rapidly followed 
by asphyxia, fall on the ground with a few convulsions. After a 
few minutes rest the respirations would become almost normal, 
the patient would get up, start again at a walk, to have soon 
